Automatic Quadrature Phase Generator

M.-H. Sun and H.C. Lin (USA)


Quadrature Phase Generator, Wireless Communication,Phase Lock Loop


Incorporating the Phase Lock Loop (PLL), an automatic Quadrature Phase Generator for modern wireless communication system is proposed. The automatic quadrature phase generator contains a Voltage Control Oscillator (VCO), a Phase Detector, a VCO Output Buffer, a Low-pass filter, and a voltage regulator. An ac signal is fed to the first input of a phase detector. The output of the VCO is fed to the second input of the phase detector to lock the frequency and has /2 phase shift with respect to the first input signal. If desired, more than two PLL can be connected in tandem, and multiples of /2 phase shift signals can be obtained. The power consumption is 17.5mW for simulating the proposed circuits using a 0.25-m CMOS technology from a 3-V supply, and a breadboard circuit has been built and measured with power consumption 25mV from a 5-V power supply.

Important Links:

Go Back